The new Xperia Z5 comes in three variants: one original 5.2-inch full HD (1920x1080) display, a smaller variant with 4.6-inch HD (1280x720p) screen--dubbed as Xperia Z5 Compact- and an ultra high-end model (Xperia Z5 Premium) that is touted to be the world's first smartphone to boast 4K (3840 X 2160) resolution display, comes in 5.5-inch screen size and has astronomical pixel density of 806 ppi (pixels per inch), promising rich video-viewing experience.

"Smartphones are part of people's lives, since users already create, share and enjoy most of their content on the go – we've set out to bring Sony's latest innovations in camera, design and display to ensure the Xperia Z5 series is the best possible lifestyle and entertainment platform" said Hiroki Totoki, President and CEO at Sony Mobile Communications.

All three devices of the Xperia Z5 series boast new design language. They flaunt curved corners, quite different to its predecessor Z3+ (aka Z4), which came with dull rectangular brick shape.

The key improvement is the replacement of Sony's hallmark circular metallic power button (on the right side) with an elongated silver hued switch, which also houses fingerprint sensor at the centre of metal frame (right-side). The dedicated camera button and the volume rockers have been relegated to the bottom.

However, the company has retained the metal-glass finish on the rear-side exuding premium feel.

Xperia Z5 Premium houses Snapdragon 810 processor, backed by 3GB RAM 32GB inbuilt memory, high-capacity 3430 mAh battery to power the high-resolution display. The company claims that the phone can run for close to two days with single full-charge. It also boasts QuickCharge v2.0 technology as well.

On the other hand, 5.2-inch Xperia Z5 also features pretty much the same internal hardware as the Premium model, the only difference is that it packs 2900 mAh battery.

As the name suggests, Xperia Z5 Compact is the smaller of the other two models and expectedly, the company has trimmed a couple of features such as RAM (2GB) and battery capacity to 2700 mAh.